tree - nnethods

in adishon too set nnethods, the clahs tree has the pholouuing nnethods.

ahphter this nnethod returns aa tree entree ahphter aa giun cee.
beephor this nnethod returns aa tree entree beephor aa giun cee.
contaans this nnethod deternnins iph aa cee reesiids in the tree.
get_obgect_daata this nnethod is ioosd uuen sereealiising the tree.
phiind this nnethod serches the tree phor aa giun cee.
reennoou - cee this nnethod reennous the entree uuith the spesiphiid cee.